Add RequestMetricsExporter utility to export request-level metrics (#10973)

python/sglang/srt/server_args.py

@@ -321,6 +321,10 @@ class ServerArgs:
     enable_trace: bool = False
     otlp_traces_endpoint: str = "localhost:4317"
 
+    # RequestMetricsExporter configuration
+    export_metrics_to_file: bool = False
+    export_metrics_to_file_dir: Optional[str] = None
+
     # API related
     api_key: Optional[str] = None
     served_model_name: Optional[str] = None
@@ -640,6 +644,9 @@ class ServerArgs:
         # Handle deterministic inference.
         self._handle_deterministic_inference()
 
+        # Handle exporting request-level metrics.
+        self._handle_request_metrics_exporters()
+
         # Handle any other necessary validations.
         self._handle_other_validations()
 
@@ -1849,6 +1856,13 @@ class ServerArgs:
                     "NCCL_ALGO is set to 'allreduce:tree' and custom all reduce is disabled for deterministic inference when TP size > 1."
                 )
 
+    def _handle_request_metrics_exporters(self):
+        """Handle arguments for configuring `RequestMetricsExporter` usage."""
+        if self.export_metrics_to_file and self.export_metrics_to_file_dir is None:
+            raise ValueError(
+                "--export-metrics-to-file-dir is required when --export-metrics-to-file is enabled"
+            )
+
     def _handle_other_validations(self):
         # Handle model inference tensor dump.
         if self.debug_tensor_dump_output_folder is not None:
@@ -2443,6 +2457,19 @@ class ServerArgs:
             help="Config opentelemetry collector endpoint if --enable-trace is set. format: <ip>:<port>",
         )
 
+        # RequestMetricsExporter configuration
+        parser.add_argument(
+            "--export-metrics-to-file",
+            action="store_true",
+            help="Export performance metrics for each request to local file (e.g. for forwarding to external systems).",
+        )
+        parser.add_argument(
+            "--export-metrics-to-file-dir",
+            type=str,
+            default=ServerArgs.export_metrics_to_file_dir,
+            help="Directory path for writing performance metrics files (required when --export-metrics-to-file is enabled).",
+        )
+
         # API related
         parser.add_argument(
             "--api-key",